Cisco iOS version naming rules

First of all, the iOS operating platform,c2500, c2600, c4500, c2950 represent the hardware platform that runs this iOS, for example: C2500 refers to the 2500 series routers. Second, look at the iOS version, iOS has the major version number: 11.0, 11.1, 11.2, 11.3, 12.0, 12.1, 12.2, 12.3, 12.4, and so on, these major version numbers are equivalent to the version of Windows Win98, Win2000, WinXP, Win2003. When Cisco publishes a major version of iOS, it will maintain it (fix bugs only, not add new features), maintain the version number by 1 per maintenance. For example , "121-27" in C2500-is-l.121-27.bin means the major version number is 12.1and maintained 27 times. When a major version of iOS is released, Cisco releases a beta version of the next version of iOS based on that major version, with the word "T" appended to the iOS name, for example: C2500-is-l.122-15.t16.bin, which becomes version 12.3 when it is officially released.

Cisco IOS Software naming convention simple introduction: aaaaa-bbbb-cc-dddd. EE

• 1. AAAAA This set of characters is the hardware platform that the description file applies to,
• 2. BBBB This set of characters is a description of the features contained in this iOS,
• 3. CC This set of characters is the iOS file format,
• 4. DDDD This set of characters is to indicate the iOS software version,
• 5. EE This is the suffix of the iOS file.

First, "AAAAA" hardware platform character groups such as: (Here we do not list, only a few representative)

• C2600 2600 Series Routers
• C2800 2800 Series Routers
• C54SM Catalyst RSM/VIP
• ics7700 ICS7700
• mc3810 MC3810 Multi-service access hub
• Regen 15104 Optical Networking System
• RPM MGX 8850 rpm
• RSP 7500 Series Routers
• VBR 7200 UBR7200 Universal Broadband Router
• VG200 VG200 Voice gateway and so on.

second, "BBBB" represents a string of attributes we say a few commonly used, often will see:

• A Advanced Peer-to-peer Networking (APPN) feature
• Boot boot image
• J Enterprise
• I IP
• Ipbase IP BASE
• i3 simplified IP, no BGP, EBP, NHRP
• i5 IP with VOFR
• K8 IPSec 56
• K9 IPSec 3DES
• o iOS Firewall
• O3 with intrusion detection system IDs, SSH firewall
• P Plus
• S Plus (NAT, IBM, VPDN, VoIP)
• V VIP
• V5 VoIP
• X3 Voice
• 56 56-bit encryption

The first "C" of the "CC" format character group indicates which router memory type the image is executed in.

• F Flash, memory
• M RAM
• R ROM
• L Run time positioning

If you are trying to remove a flash card (flash card) from a router, you can see what this character is. If it is f, then the software is executed directly from the flash, which requires the installation of flash memory so that the iOS software can run. If it is m, then the router has read the iOS software from Flash (flash memory) and is running it from RAM after compression. After the router normal boot up, you can safely remove Flash. The second "C" shows how to compress the

• Z Zip compression
• X mzip Compression
• W STAC Compression

Iv. "DDDD" version description character group

Indicates the version number of the iOS software

Five, ". EE "filename also has a suffix

such as:. Bin or. Tar

Example: "Rsp-jo3sv-mz.122-1.bin", RSP is a hardware platform (Cisco 7500 series).  The JO3SV is an enterprise-class (J), an IDs-equipped firewall (O3), an IP enhancement with Nat/voip (s), and a universal Interface Processor VIP (v).  MZ indicates that it is running in RAM memory of the router and is compressed with zip. 122-1 indicates that Cisco IOS Software release 12 (2) 1, which is the first maintenance version of major version 12 (2): Bin is the iOS software suffix.

Cisco iOS version naming rules